1. Technical Field
The present invention relates to manufacturing of semiconductor wafers, and more particularly to a device for the injection of CMP slurry used in chemical mechanical polishing.
2. Description of Related Art
Currently, for making a semiconductor chip, tens of thousands of transistors are structured through three-dimensional wiring or multilayer wiring. Therefore, it is important to treat semiconductor wafers using chemical mechanical polishing (CMP) so as to flatten and prepare the surface of the wafer for subsequent procedures.
As shown in FIG. 7, typical CMP equipment introduces a large quantity of slurry 80 onto the surface of a rotating polishing pad 81. The slurry 80 then flows between a wafer 82 and the polishing pad 81 as the latter rotates, so as to polish, clean and lubricate the wafer and condition the surface of the wafer as desired.
However, since the typical CMP equipment introduce slurry onto the polishing pad in a concentrated manner, a large part of the introduced slurry may flow to where is out of the polished area, and the slurry is unlikely to be distributed evenly. This not only causes waste of slurry, which is against to economical consideration and environmental consideration, but also has adverse effects to polishing performance.